Mechanical motion



M. O. CRAWFORD MECHANICAL MOTION Sept. 9 1924. 1,507,908

Filed Feb. 14 1922 3 Sheets-Sheet 1 -llillllli I lllnlll Il I I sept. 9, 1924. 1,507,908

M. O. CRAWFORD MECHANICAL MOTION Filed Feb. 14,1922 5 sheets-sheet z sept. 9, 1924. 1,507,908

' M. O. CRAWFORD MECHANICAL MOTION Filed Feb. 14, 1922 s sheets-sneer s Patented Sept.v 9, 1924.

, *UNITED lSTATES MATTHEW of CRAWFORD, or BELT/TONI), IOWA.

' ing the time that the crank arm 'onfthe Mnc'HANIoAn MOTION;

Application filed February 14, 1922.*` Serial No. 536,579.

To all whom t may concern.'

, Be it known that I, MATTHEW O. GRAW- l FORD, a citizen of the United States, Aand a resident of Belmond, in the county of Wright and State of Iowa, have invented" a certain new and useful Mechanical Motion, of which the following is a specification.

The object of my invention is tok provide a mechanical motion of simple, durable and inexpensive construction, especially designed for use in transmitting power from a pulley.

or 'the likel to a reciprocating motion, such for instance `as is necessary to operate' an ordinary. pump, and at the same time provide for a considerable speed'reduction from the pulley to the reciprocating member, and. to accomplish this result with a minimum,

number of gears of minimum size. More specifically it is my obgect to provide a mechanical motion of this class that is especially adapted for use as a pump jack, and in this connection it is my obj ect tolprovide, as part of my improved mechanical motion, a pump jack of simple, durable and inexpensive construction which may be clamped directly to the pump stock and does not need a separate support, and in which the center of the pulley may be in line with the center of the Apump stock to avoid twisting strain .as applied tothe frame of the pump jack; and further to provide the necessary speed reducing gears, which gears may bel of minimumsize and so located and arranged as to be capable of lbeing compactly assembled to produce a ,pump

jack of light weight and inexpensive Vconstruction occupying a minimumv amount of s ace. y

pMore specificallyit is my object to providefal mechanical motion whereby'v power maybe transmittedfrom the rotary shaft to a reciprocating member, such forfinstance as a'pump rod, yby means of a round eccen,

trically mounted spur gear, and an elliptical spur gear in mesh therewith and y having twice the number'of teeth, sotha't by means of these two gears thev speed of rotation is reduced one-half, andat the rsame time the"` reciprocating motion as-applled tothe pump rod-is made relatively; slow during'the up and down strokes, and relatively rapid d urelliptical gear 'is passing dead center, and whereby the maximum amount-Of,k power applied to the driving shaft willbe available during the pumping stroke, and wherebythe time consumed duringV such parts of the-strokes asv are noteffective in'pumping will be minimized. v j A further object is to provide a mechanical motion of thisv character vin, which the shaft.,

upon -which the driving pulleyl is rotatably mounted, rotates `in the same direction as PATENT' OFFICE, f

the pulley, but at a reduced speed, thereby reducing the amount of frictionand wear between the pulley and the driving shaft.- i' My :in'vention consists in the construction,

templated' are attained, als'l hereinafter more fully set forth, pointed out in my claim, and illustrated in the accompanying drawings, inwhich: i i pi n Figure lijshows a toporplan view of my improved mechanical' motion applied to a parts Vof tical gear arranged atan angle of, approximately forty-five degrees relative to its position as shown in Figure 3.

' arrangement and combination' of the various parts of the device, whereby the objects con- Figure 5 shows `a side elevation'of my' .Figure 6 shows a-front elevation the same.

. Referring to the accompanying drawings,-

`improved mechanical motion applied't'o va lpump and a driving belt; and a I have used the reference numeral 2O to indicate apump stock having a reciprocating piston rod 21 connectedwith ya cross head 22 from which the two crank arms 23 are extended downwardly 'for driving puipos'esl Detachably'mounted upon the pump vstock is the frame body 4;, one side ofwhichv'is ,y

shaped to receive -theadjacent side 'of the` pump` stock. Opposed to the bodygpforf sideof the pump stockv and'to Mounted inthe body portion Liis a rotate able Vdriving shaft V3 to which isnfixed'at' Lone Ve-nd a crank 13, and-at thejotherv end an .elliptical spur toothed gear 2, the?4 latter of which has a crank pin 26 c'onneotedto the: adjacentarm it 23,'` and thecrankh'l has 'a crank'pin 27 connected Ato the opposite/one "fof the arms23i@ '2 ltion is clamp '24 to engage'vthe opposite-1v y l be firmly `:clamped tothe body portion 4 by bolts'25;

Thus, the said pins 26 and 27 are made to ointlyl ope-rate'ithe"reeiprorating pump rodw'li'en the Shaft 3 is; rotated.

Formed on the trarne Il are"the"'1"`ra:1ne ineinbere 28, in the outerrfendsfofwhichis rotatively mounted the pulley shaft 12, and on this pulley shaft 12 are f'rotatably inounted the pulley 5 and the pulley 6, the latter is Jformed with'aeleeye"upon"'which isA formed a small spur toothed gear. Mounted in thev traine'in'erhber 28 is a rotatable shaft '9,1 on'one end ofwvliichJ is finedv the spur gear 8 iin'ielsh with'the-"gear 7, and' on the other,1 end is fixed the/ Small spur., 'gear '1 0 in ineSli 'with `a. larger Spur A gear 1 1 vwhicli is keyed-` vtofthe'Shaft 1 2.

By this ar'ian'genientof parts', it `i S 'o byi-ous that theent'ire'deyicefinay'be clanipedto a pump "etocl readily, easily? 'and 'quiclily,' and dries not need anyeeparateeupport.

straight line throughf the pump 'f fstfock -so thatl there isno side; pull or strainupon the frame- H l Furthermore, the yspeedofL the pulleyf 6 will be twice freduced as appliedto 'the'v'shaft 12,and'iurtherinora 1the directionv of rotation of the shaft 12 will bef'theeaine vas the direction of rotation 4o/t the pulleyt, so that the vfriction and wear of the pulley iupon the shaft 12 will bevreduced to inininium.

Fory the4 purpose of Atrauernitting y'power JfromV the sliaft12 to--theShafti, have provided two meshing gear wheelfsone, indicated ygenerally Yby thehsynibol y1, 'is a circular spur -tooth gear wheel,l but -it is :mounted eecentrically upon the' shaft 12. The other, indicatedi'byf thevnumerial 2,'is substantially #elliptical in i shape-and has twice-fthe number of-.gearv-teeth; Aand as these two gear wheelsa`re' l eo'netantly --in meeln itt isl obvious' that the, -ellipticaljgear wheel is rotated at one-halt the average -speedot the eccentric gear wheeh f ln order to providetor the-pertectinten lmeshing f' of 'the -gear .teeth of 'the elliptical and leccentric vi-gears,-during the 'entire revo- Ilution, I have -torin'ed 'the f'eecenitricY gear teeth f on radial :lines from -thevcenterfthereof with the teeth equally-spaced apartff'as in an ordinary "spurl f gear.

For forming the yte'et Y v'gea-r,` L proceed'as ifollows;

The tour 1 teeth, lthatfare #shown-1in IFigure 3;- at-ftheftop centerbottom center; left side ntenter and right?. s'idej -renter are allrformedin'flineeradial' 'to thef axis of :..th'ez ellpticall'gear, In ritorni-' '.gnthefirsttoothirb enter "jftoothfjql dvelop f r the i'piteh cente Slfthereofjlfas;follows;

h 'onvfthe elliptical ted 'lines commence onen-tati i arranged :as

row-targata? center of the spur gear 1, andthe other line -7`coininenc`es "at Afthe shaft y center. Then a "ceirter isiorined atthe pitch line of the "tooth'rspace which space will, during the "frotation ofthei-'gea1s,"'receiye this first tooth through which the projected lines h are 'fellow-n' in the elliptical gea-r. I then develop or meaeurethe difference in angularity be- "twe'en thev two* projected lines 71, on the v gear 1 as shown in Figure 3. I then draw a line from the center ot the elliptical gear dthrough the pitch center ot the teeth Von the elliptical gear under consideration.'A then "project another line through the pitchcenter of t lie-saidtooth on the elliptical gear, the angularity 'of which vcorresponds to the `di "e ifencev of angularity between the two 'proje'ctedy lines 7L on the gear 1, and this Y. V'second one'of the projected lines L on l vthe, gear y2 'is 'extended- -to` pointV directly f below the center of the elliptical gear, and itisv the'point where this second -oneof the projected lines 7L strikes the Verticalline throughythe center' ofv the gear 2, as `shown inFi'gure t, that is used as a center upon which "the 'sides of the teethunder consideration' are developed.

Indeyeloping the next tooth on the ellip tical. gear,'the one-` through which' the progA Ijected linee g are extended,'lliproceed'as 95 follows: Y Coinniencing at'v the next 'tooth space on ythejgear 1, it beingthe one throughfwhich ;the projected lines fg are'drawn, and being vthe-*saine one that is designed to receive the-190 tooth onthe 'ellipticalv gear through which the. `projected linesl ff/ `are extended, I project two lines marked gfon the gear 1, one o them ybeingsr `radial tothe center of the Wgearl 1, yand the'lothergbeing radial to the 4-ehaftotthegear 1, andfdeternine the degree v of angularity between these two line-S. l -fthen place the projected lines g upon the `@gear 2, to 'the toothk under consideration` 'l having Ithe saine degree-of angularity-f'with relation y,toeach vother ae 'the projected linesv g on the gear 1. One of these lines is radial 'tolthe center of the "gear 2, and the end o fqthei other strikes the ,vertical lne. `vtlirfjughgthegear 2 ata pointbelowthe cen ;er,-a`ndit is tliis -po int thatxisused'as a centeruponfwhich the sides/"of the tooth. are developed. A 'Each tooth ter vof the "gear 2 is developed in the -Y saline manner, and thel projected lines-` respectiyely areindicatedI in Figure 3 by the symbole c4 Y7a, cnycazn5 n0-7 3, ccbgayaar n I Y :In thepracticaloperation of `this part ott-V he device comp'rising the eccentric and eliptiealfjgears, `iteis-gV obvious that theegear. 1 illlmake "two revolutions Ito* `each ire-velu IEE i' vertical, the speed of the gear 2 that has been previously described, the gear teeth on the eccentric and elliptical gears will mesh accurately throughout the entire revolution, and this is made apparent upon examination' of Figure 4.

Another material advantage gained by thev use of my improved gearing is that during that part of the pump piston stroke in which the movement of the crank pin 26 is relatively horizontal, the speed of travel of the crank pin will be relatively rapid, whereas during that part of the stroke of the movement of the crank pin 26 which is relatively travel of the crank pin will be relatively slow.

Hence, during the effective stroke of the pump piston, or other object to which this device is applied, there will 'be greater power due to the relatively slow movement than there is during the part of the movement which is not what might be ective part of the stroke.

I claim as my invention: j In a device of the class described, comprisJ inga frame,

termed the stock,a crank shaft mounted 'in the frame, a crank on. one end thereof, a mounted in the frame, mounted on the edly a pulley rotatably pulley shaft, a spur gear fixconnected to the pulley, a spur gear ixed to the pulley shaft, a train of gears ar-f ranged to transmit power from the-first mentioned spur gear to the second spur gear the said second spur gear being fixed eccentric' to the pulley shaft, and an elliptical gear iXed to one end of the crank shaft andy in means for securing the frame vto a support, such for instance as a pump pulley shafty 

